Method of making recloseable flexible bag

ABSTRACT

The invention provides a recloseable bag formed of flexible sheet material comprising a front wall and a rear wall sealed together adjacent at least one of a pair of opposite edges thereof, said bag including in a wall thereof an elongated deformable member, such as a metal wire, extending transversely of said edges to provide for repeated closure of the bag, the ends of the elongated member being spaced from said edges of the bag and the sheet material between the ends of the member and the said edges of the bag being removed. The invention also provides a method of producing said bags.

United States Patent [191 White METHOD OF MAKING RECLOSEABLE FLEXIBLEBAG [75] Inventor: David B. White, Willowdale,

Ontario, Canada [73] Assignee: E. S. & A. Robinson (Canada) Ltd.,

Toronto, Ontario, Canada 221 Filed: Sept. 12,1972

21 Appl. No.: 288,434

[52] US. Cl. 93/35 DS, 93/1 TS, 93/35 R [51] Int. Cl B31b 1/90 [58]Field of Search 93/35 DS, 35 R, 1 TS, 76

[56] References Cited UNITED STATES PATENTS 2,777,491 1/1957 Ashton etal. 93/35 DS X 2,897,729 8/1959 Ashton et a1. 93/35 DS X 3,283,6721l/1966 Mueller 93/35 DS 3,417,675 12/1968 Ausnit.. 93/8 WA 3,687,3578/1972 Hansen 93/35 DS X 1 Jan. 14, 1975 3,772,968 11/1973 Ruda 93/35 DSPrimary ExaminerRoy Lake Assistant ExaminerJames F. Coan Attorney,Agent, or FirmStevens, Davis, Miller & Mosher [57] ABSTRACT Theinvention provides a recloseable bag formed of flexible sheet materialcomprising a front wall and a rear wall sealed together adjacent atleast one of a pair of opposite edges thereof, said bag including in awall thereof an elongated deformable member, such as a metal wire,extending transversely of said edges to provide for repeated closure ofthe bag, the ends of the elongated member being spaced from said edgesof the bag and the sheet material between the ends of the member and thesaid edges of the bag being removed. The invention also provides amethod of producing said bags.

13 Claims, 14 Drawing Figures PATENTEDJAN14I975 3,859,895

1 SHEET 2 OF 9 F IG.3.

PATENT EU JAN 1 4mm SHEET 3 OF 9 PATENTED JAN 1 4 I975 SHEET u 0F 9PATENIEDJA" i 41% a; 859,895

SHEET 9 BF 9 METHOD OF MAKING RECLOSEABLE FLEXIBLE BAG The presentinvention relates to bags formed from flexible sheet material,particularly thermoplastic sheet material, such as polyolefins,preferably polyethylene and a method of producing such bags. Inparticular the present invention relates to recloseable flexible sheetbags which can be repeatedly closed subsequent to the breakage of thetop seal thereof.

Flexible sheet bags such as thermoplastic sheet bags have heretoforebeen produced inter alia by continuously passing a pair of superimposedlayers of the sheet material, which layers are suitably formed bylongitudinally folding a single sheet of the thermoplastic material,along a defined path to a cutting and sealing station where the layersare cut and sealed, suitably by a vertically moving hot knife,transversely to the direction of motion of the layers in the definedpath, which hot knife cuts and seals the sides of the bag to form sideseams. During the passage along the defined path of the layers to thecutting and sealing station they may be longitudinally sealed adjacentto one end thereof to provide a header for the bag, the bottom of thebag being left unsealed for the insertion of the contents into the bag.When the bag has been filled the bottom of the bag is subsequentlysealed. However, such bags have the disadvantage that once the top sealis broken to gain access to the contents of the bag the bag is notrecloseable.

A recloseable bag has been shown in US. Pat. No. 2,973,131 to Mead, etal, which includes the presence of an opening and closing meansincluding a tab which extends across the bag adjacent the top endthereof, the tab extending beyond the side seams of the bag andincluding wire therein as a deformable member. While this tab iseffective in providing for repeated reclosing ofthe bag, the closuremeans has to be attached to each individual bag after it has beenfabricated, i.e., after the cutting and sealing station whichnecessitates increased handling of the bag and thus substantiallyincreases the cost of the production of the bag.

British Pat. No. 1,263,761 published Feb. 16, 1972 to TCF Canada Ltd.discloses a recloseable bag in which the bendable metal wire extendslongitudinally of the bag to provide for reclosing of the bag.

The present invention provides a bag which includes a closure means forrendering the same repeatedly openable and closeable after the ruptureof a seal in which less material is necessary to provide the closuremeans and in which the closure means can be incorporated into the bagduring the course of its conventional manufacture without increasedhandling thereof.

It has now been found according to the present invention that byapplying and sealing a continuous elongated deformable member,particularly metal wire, to the outer face of one of the layers,particularly in the aforesaid process, the member being disposedsubstantially parallel and adjacent to but spaced from an edge duringits passage along the defined path and by punching holes through saidlayers where the member intersects the portion of the layers whichare-subsequently cut at the cutting station whereby the knife does nothave to cut through the member thus avoiding damage thereto, a flexiblebag is produced including a closure means rendering the samerecloseable. In addition thereto it is found that by providing suchholes in the bag communication may be provided between the interior ofthe bag and the external atmosphere whereby it is possible to avoidentrapment of air in the bag when the bottom of the bag is subsequentlysealed.

According to the present invention there is provided in a recloseablebag formed from a flexible sheet comprising a front wall and rear wallsealed together at or adjacent at least one of a pair of opposite edgesthereof, said bag including in a wall thereof an elongated deformablemember extending transversely of said edges to provide for repeatedclosure of the bag, the improvement in which the ends of the elongatedmember are spaced from said edges of the bag, the sheet material betweenthe ends of the member and said edges of the bag being removed.

In accordance with one embodiment of the present invention the pair ofopposite edges are the side edges thereof both of which are sealed, theelongated deformable member extending transversely of said side edgesadjacent to either the top orbottom of the bag.

In a particularly preferred embodiment ofthe present invention the frontwall and the rear wall are sealed together adjacent the top thereof,said wire providing for subsequent repeated closure of the bag afterrupture of the seal adjacent the top thereof and said removed sheetmaterial providing for communication between the interior of the bag andthe outside atmosphere. The bag of the embodiment may be in its fillableform and has a sealable open bottom and is suitably provided with a flapto enhance the sealing of the bottom thereof or alternatively the bagmay be filled with the goods to be packaged, such as cookies, and has asealed bottom. The bag may also be provided with. a reinforced headerattached to the top thereof as is conventional.

In an alternative embodiment of the present invention the bag has aclosed bottom, said wire being disposed in a flap portion of the rearwall extending beyond the front wall.

Again, the bag of this alternative embodiment may be in fillable formand has a sealable top or alternatively the bag may be filled with thegoods to be packaged and has a sealed top.

In a still further embodiment of the present invention the pair ofopposite edges are bottom and top edges of the bag at least the bottomedge of the bag being sealed, the deformable member extendingtransversely of said edges and longitudinally of the bag suitably in thecenter of thereof in a similar manner to the aforesaid British Patent.

The present invention also provides a method of making a recloseable bagof a flexible sheet material which comprises continuously passing twosuperimposed layers of said sheet material along a defined path to asealing station and a cutting station where said layers are sealed andcut transversely of their direction of travel to form a pair of oppositeedges of said bag and during passage along said defined pathcontinuously passing an elongated deformable member to and sealing saidwire on the face of one of said layers substantially transverse to saidedges and continually punching holes through said layers at the pointswhere the member intersects the portions of the layers which aresubsequently cut at the cutting station.

In forming the bag with the deformable member transverse to the sideedges thereof the superimposed layers may be cut and sealedsimultaneously by a hot knife to form a weld or can be cut subsequent tosealing using a cold knife in which case the seal generally liesslightly inwardly from the side edge of the bag.

In providing the bag according to the preferred embodiment of thepresent invention the layers during passage along the defined path arecontinuously longitudinally sealed adjacent one edge thereof to form thetop of the bag, the elongated member being sealed on the outer face ofone of said layers essentially parallel to and spaced from saidlongitudinal seal.

In providingthe bag according to the alternative embodiment of thepresent invention the superimposed layers are continuously formed bylongitudinally folding a single sheet of said material to provide a flapportion in one of such layers extending beyond the other layer, saidelongated member being sealed in the adjacent flap portion.

In forming the bag with the deformable member transverse to the bottomand top edges of the bag the seals on the side edges of the bag areformed without cutting or the superimposed layers are in the form of acontinuous tube. The bottom edge only of the bag may be cut and sealedusing the hot knife as the top edge must be provided open for theinsertion of the contents of the bag and is then sealed. This may beachieved by having the sealing station separate from and upstream of thecutting station, a cold knife being used at the cutting station.Alternatively this may be achieved by the use of a hot knife providing aweld at the bottom of the bag which operates on a timed sequencealternately with a flying knife so as to weld and cut the superimposedlayers alternately.

The flexible material is preferably a thermoplastic material whence theside, top and bottom seals of the bag are suitably heat seals, the sealssuitably being produced by a hot knife. Particular thermoplasticmaterials which may be mentioned include polyolefins, particularlypolyalkylenes, preferably lower polyalklylenes and more preferablypolyethylene. The elongated deformable member is preferably a metalwire.

In accordance with one embodiment of the present invention the wire issealed to the surface of said layer by means of an adhesive tape whichis continuously passed to the face so as to be superimposed on the wireand the tape is subsequently pressed into contact with the face to sealthe wire to the In another embodiment of the present invention, wherethe sheet material is a thermoplastic material, a thermoplastic strip iscontinuously passed to the face so as to be superimposed on the wire andthe strip is heat sealed to the face to seal the wire to the face.

In yet a further embodiment of the present invention where the sheetmaterial is a thermoplastic material, a gusset is continuously formed inthe layer containing the surface, the wire being continuously introducedinto the gusset and heat sealed therein.

The present invention will be further illustrated by way of theaccompanying drawings in which:

FIG. 1 is a perspective view of a bag according to one embodiment of thepresent invention;

FIG. 2 is a vertical section through a bag according to an alternativeembodiment of the present invention;

FIG. 3 is a perspective view of a bag according to yet anotherembodiment of the present invention;

FIG. 4 is a perspective view partially broken away in vertical sectionof a bag according to a still further embodiment of the presentinvention;

FIG. 5 is a schematic perspective view of an apparatus useful in makingthe bag according to the embodiments of the invention set forth in FIGS.1 and 2;

FIG. 6 which is on the same sheet of drawings as FIG. 1, is a detail ofthe apparatus according to FIG. 5 showing a method of attaching the wireto the bag according to one embodiment of the present invention using anadhesive tape;

FIG. 7 which is on the same sheet of drawings as FIG.

1, is a detail of-the apparatus according to FIG. 5 showing a method ofattaching the wire to the bag according to another embodiment of thepresent invention using a thermoplastic tape;

FIG. 8 is a detail of an apparatus according to FIG. 5 showing a methodof attaching the wire to the bag according to yet a further embodimentof the present invention by means of a gusset;

FIG. 9 is a schematic perspective view of an apparatus useful in makingthe bag according to the embodiment of the invention set forth in FIG.3;

FIG. 10 is a schematic perspective view of an apparatus useful in makingthe bag according to the embodiment of the invention set forth in FIG.4;

FIG. 11 is a perspective view of a bag according to another embodimentof the present invention;

FIG. 12 is a perspective of a bag similar to that in FIG. 11 but with adifferent bottom edge seal;

FIG. 13 is a schematic perspective view of an apparatus for making thebag of FIG. 11; and

FIG. 14 is a schematic perspective view of an apparatus useful formaking the bag of FIG. 12.

Referring to FIGS. 1 and 2 the bag which is suitably formed ofpolyethylene has a front wall 1 and a rear wall 2 and has heat seals 4along the side edges thereof and a heat seal 5 adjacent the top thereof.The bottom of the bag has a flap 6 and is open. The bag may be filledthrough the open bottom with the desired contents and the flap thenturned up and heat sealed as at 7. In the unfilled state with the openbottom, the flap 6 has holes 7 therein by which the unfilled bag may besuspended. At the top of the bag there is suitably provided a flaseheader 9 which includes a hole 10 by which the filled bag may besuspended after the flap 6 has been scaled.

Referring particularly to FIG. 1 the bag includes a metal wire 11 heldin place on the front wall 1 by a tape 12 which may be an adhesive tapeor a thermoplastic tape which thermoplastic tape is heat sealed to thefront wall 1 of the bag. At the side edges of the bag semi-circularholes 13 have been punched out which has also removed the ends of thewire 11 and also provides communication of the interior of the bag withthe external atmosphere and thus prevents entrapment of air when the bagis closed by sealing the flap 6.

Referring specifically to FIG. 2 in an alternative embodiment the wire11 is held in place in a heat sealed gusset 14 in the front wall of thebag.

The bags of FIG. 1 may be made with the apparatus of FIG. 5 incombination with that of FIG. 6 or 7 and that of FIG. 2 with theapparatus of FIG. 5 in combination with that of FIG. 8.

Referring to FIG. 5 sheet polyethylene 20 is withdrawn from a roll 21.The sheet 20 contains printed portions 22 which form the false header 9in the finished bag. The sheet 20 is folded at folder 23 intosuperimposed layers 24 and 25, the lower layer 25 extending beyond theupper layer 24 to form the closeable flap 6 in the finished bag. Thefolded sheet 20 passes from the folder 23 over tensioning rolls 26 andis contacted by a header edge sealer 27 to provide the seal 5 in thebag. The flap 6 in the lower layer 25 has holes 8 punched therein bypunch 28 and the false header 9 has holes punched therein by punch 29.The folded sheet 20 finally passes through nip rolls 30 and verticallyreciprocating hot knife 31 to provide the edge seals 4 in the bag.Instead of the hot knife 31 the heat seal may be made separately at oradjacent the edge 4 and then separately cut with a knife. The procedureas set forth heretofore constitutes the standard method of making thebag. In accordance with the present invention the metal wire 11 is fedto the upper layer 24 of the sheet 20 from a reel 32 and is sealedthereto by the techniques shown in FIGS. 6, 7 or 8.

Referring specifically to FIG. 6, adhesive tape 12 is fed from reel 33to overlay the wire 11 on the layer 24 and tape 12 is pressed intosealing contact with the layer 24 by pressure roller 34.

Referring to FIG. 7 thermoplastic tape 12 is passed from reel 35 tooverlay the wire 11 on the layer 24 and g is maintained in contact bypressure roller 36 and heat sealed to the layer 24 by hot pressureroller 37.

Referring to FIG. 8 a gusset 14 is formed in the upper layer of thesheet 24 by a pair of rigid arms 38 and 39. Arm 39 extends between thelayers 24 and and arm 38 extends into the gusset 14. The metal wire 11from reel 32 is fed into the gusset 14 and the gusset 14 is then heatsealed by hot pressure roller 40.

Referring once more to FIG. 5 a punch 41 punches out holes 42 in thesheets 24 and 25 at the points where the wire 11 intersects the portionof the layers 24 and 25 to be cut by the hot knife 31, thus avoidingdamage to the knife during the cutting operation.

The bag of FIG. 3 comprises a front wall 1 and a rear wall 2 and hasheat seals 4 along the side edges thereof. The top of the bag is openand the bag may be filled through such top opening with the desiredcontents and the opening subsequently heat sealed. The rear wall 2includes a flap 50 having a metal wire 11 held in place on the insidesurface thereof by a tape 12 which may be an adhesive tape or athermoplastic tape, the latter being heat sealed to the flap 50, andsemi-circular holes 13 are punched at the side edges of the bag, whichholes have removed the ends of the wire 11. The flap 50 serves toreclose the bag when the sealed opening is broken to remove a portion ofthe contents.

Referring to FIG. 4, the flap 50 is double folded at 51 and 52. The topof the bag is open and is filled with the desired contents through theopening which is then heat sealed. Metal wire 11 is attached to the flap50 and is held in position on the inside surface of the flap 50 by atape 12 as shown in FIG. 3 and semi-circular holes 13 are provided as inFIG. 3. The flap is thus of a double thickness.

The bag of FIG. 3 may be made with the apparatus of FIG. 9 in whichpolyethylene sheet 20 is withdrawn from a roll 21 over tensioning rolls3 and is folded at folder 23 into superimposed layers 24 and 25, thelower layer 25 extending at 53 beyond the upper layer 24 to form theflap 50 in the finished bag. The folded sheet 20 passes from the folder23 over tensioning roller 26 and then through nip rolls and verticallyreciprocating hot knife 31 to provide the edge seals 4 in the finishedbag. Metal wire 11 is fed to extension 53 of the lower layer 25 from awire reel 32 and sealed thereto 31 thus avoiding damage to the knifeduring the cutting operation.

The bag of FIG. 4 may be made with the apparatus of FIG. 10 in whichpolyethylene sheet 20 is withdrawn from a roll 21 under tensioning rolls3 and during passage between a lower and upper tensioning roll 3 iscontacted by rigid folding arm 54 which institutes the fold 51 into oneedge of the sheet 20 and then rigid folding arms 55 which introduce thef0ld.52 into the folder portion 51 formed by the arms 54. The sheet 20so folded is further folded at folder 23 to form an upper layer 24 and alower layer 25, which upper layer 24 extends beyond the lower layer 25at 53 to form the double width flap 50 in the finished bag of FIG. 4.The folded sheet 20 passes from the folder 23 under tensioning roll 26and then through nip rolls 30 and vertically reciprocating hot knife 31to provide edge seals 4 in the finished bag. Metal wire 11 is fed to theextension 53 of the upper layer 25 from a reel 32 and is sealed theretoby the techniques shown in FIGS. 6 or 7 as described previously. Punch41 punches out holes 42 in the extension 53 at the points where the wire11 intersects the portion of the extension 53 to be cut by the knife 31,thus avoiding damage to the knife during the cutting operation.

Referring to FIG. 11, the polyethylene bag comprises a front wall and arear wall 61 sealed adjacent the bottom edge 63 thereof by a heat seal64. The upper end of the bag is open at 65 for the insertion of thecontents thereof and is then sealed. A metal wire 66 extendslongitudinally of the bag and is held in position on the front wall 60by an adhesive or thermoplastic tape 67, the thermoplastic tape beingheat sealed to the front wall 60 of the bag. At the bottom edge 63 ofthe bag and the top edge 68 of the bag, semi-circular holes 69 arepunched out which also removes the ends of the wire 66 and providescommunication with the external atmosphere thus avoiding entrapment ofair when the bag is closed by sealing the top edge 68.

Referring to FIG. 12 the bag is identical to the bag of FIG. 11 exceptthe seal at the bottom edge 63 is a weld seal.

The bags of FIG. 11 and FIG. 12 :are produced by the apparatus set forthin FIGS. 13 and 14 wherein a continuous flattened tube of polyethylene82 is withdrawn from a supply roll 71 and has applied to one surfacethereof a metal wire 66 from a supply 72, the wire 66 being attached tothe surface of the bag by means of an adhesive tape by the techniqueshown in FIG. 6 of a thermoplastic tape by the technique shown in FIG.7. A punch 73 punches holes 74 in the tube 82 at points where the wire66 intersects the portion of the tube 82 to be cut by the cold knife 75or hot knife 77 thus avoiding damage to the knife during the cuttingoperatron.

In FIG. 13 the bottom of the bag is sealed by hot bars 76 before cuttingby downstream cold knife 75 to produce seals 64 in the bag of FIG. 11..In FIG. 14 tube 82 is alternatively cut by hot knife 77 to form thebottom edge 63 of a pair of bags each with weld seal 70 and then byupstream flying knife blade 78 on chain 79 driven by sprockets 80 intimed sequence to form unsealed open tops 65 of the pair of bags whichare subsequently sealed after insertion of the contents of the bag.

I claim:

1. A method of making a recloseable bag of a flexible sheet materialwhich comprises continuously passing a pair of superimposed layers ofsaid sheet material along a defined path to a sealing station and acutting station where said layers are sealed and cut transversely oftheir direction of travel to form a pair of opposite edges of said bag;and during passage along said defined path, continuously passing anelongated deformable member to, and sealing said member on, the face ofone of said layers transverse to said edges; and continually punchingholes through said layers at the points where the member intersects theportion of the layers which are subsequently cut at the cutting station,while at the same time punching out the adjacent section of saiddeformable member.

2. A method as claimed in claim 1 in which said layers are cut andsealed to form side edges of said bag.

3. A method as claimed in claim 2 including during .passage along saiddefined path continuously longitudinally sealing said layers adjacentone edge thereof to form the top of said bag, said elongated memberbeing sealedon the outer face of one of said layers essentially paralleland adjacent to, but spaced from said longitudinal seal.

4. A method as claimed in claim 1, in which the elongated member is ametal wire.

5. A method as claimed in claim 1, in which adhesive tape iscontinuously passed to said face so as to be superimposed on saidelongated member and the tape is subsequently pressed into contact withsaid face to seal said member on said face.

6. A method as claimed in claim 1, in which the sheet material isthermoplastic sheet material and the sealing is heat sealing.

7. A method as claimed in claim 6 in which the thermoplastic strip iscontinuously passed to said face was to be superimposed on the elongatedmember and the strip subsequently heat sealed to said face to seal saidmember on said face. i

8. A method as claimed in claim 6, in which a gusset .is continuouslyformed in the layer containing said face, the elongated member beingcontinuously introduced into said gusset and heat sealed therein.

9. A method as claimed in claim 1, in which the cutting and sealing ofthe layers at the cutting and sealing stations is effected by means of ahot knife to provide a weld.

10. A method as claimed in claims 1, in which the cutting and sealing ofthe layers at the cutting and sealing stations is effected by a separatesealing bar and a cold cutter disposed downstream thereof.

11. A method of making a recloseable bag of a flexible sheet materialwhich comprises continuously passing a pair of superimposed layers ofsaid sheet material along a defined path to a-sealing structure and acutting station where said layers are sealed and cut transversely oftheir direction of travel to form a pair of opposite edges of said bag;and during passage along said defined path, continuously passing anelongated deformable member to, and sealing said member on, the face ofone of said layers transverse to said edges; and continually punchingholes through said layers at the points where the member intersects theportion of the layers which are subsequently cut at the cutting station,said layers being cut and sealed to provide a sealed bottom edge to saidbag and an open top to said bag.

12. A method as claimed in claim 11 in which the superimposed layers arepassed along said defined path as a tube.

13. A method of making a recloseable bag of flexible sheet materialwhich comprises continuously passing a pair of superimposed layers ofsaid sheet material along a defined path to a sealing station and acutting station where said layers are sealed and cut transversely oftheir direction of travel to form a pair of opposite edges of said bag;and during passage along said defined path, continuously passing anelongated deformable member to, and sealing said member on, the face ofone of said layers transverse to said edges; and continually punchingholes through said layers at the points where the member intersects theportion of the layers which are subsequently cut at the cutting station,said layers being cut and sealed to form side edges of said bag, thesuperimposed layers being continuously formed by continuouslylongitudinally folding a single sheet of said material to provide a flapportion on one of said layers extending beyond the other layer, saidelongated member being sealed on a face of the flap portion.

1. A method of making a recloseable bag of a flexible sheet materialwhich comprises continuously passing a pair of superimposed layers ofsaid sheet material along a defined path to a sealing station and acutting station where said layers are sealed and cut transversely oftheir direction of travel to form a pair of opposite edges of said bag;and during passage along said defined path, continuously passing anelongated deformable member to, and sealing said member on, the face ofone of said layers transverse to said edges; and continually punchingholes through said layers at the points where the member intersects theportion of the layers which are subsequently cut at the cutting station,while at the same time punching out the adjacent section of saiddeformable member.
 2. A method as claimed in claim 1 in which saidlayers are cut and sealed to form side edges of said bag.
 3. A method asclaimed in claim 2 including during passage along said defined pathcontinuously longitudinally sealing said layers adjacent one edgethereof to form the top of said bag, said elongated member being sealedon the outer face of one of said layers essentially parallel andadjacent to, but spaced from said longitudinal seal.
 4. A method asclaimed in claim 1, in which the elongated member is a metal wire.
 5. Amethod as claimed in claim 1, in which adhesive tape is continuouslypassed to said face so as to be superimposed on said elongated memberand the tape is subsequently pressed into contact with said face to sealsaid member on said face.
 6. A method as claimed in claim 1, in whichthe sheet material is thermoplastic sheet material and the sealing isheat sealing.
 7. A method as claimed in claim 6 in which thethermoplastic strip is continuously passed to said face so as to besuperimposed on the elongated member and the strip subsequently heatsealed to said face to seal saiD member on said face.
 8. A method asclaimed in claim 6, in which a gusset is continuously formed in thelayer containing said face, the elongated member being continuouslyintroduced into said gusset and heat sealed therein.
 9. A method asclaimed in claim 1, in which the cutting and sealing of the layers atthe cutting and sealing stations is effected by means of a hot knife toprovide a weld.
 10. A method as claimed in claims 1, in which thecutting and sealing of the layers at the cutting and sealing stations iseffected by a separate sealing bar and a cold cutter disposed downstreamthereof.
 11. A method of making a recloseable bag of a flexible sheetmaterial which comprises continuously passing a pair of superimposedlayers of said sheet material along a defined path to a sealingstructure and a cutting station where said layers are sealed and cuttransversely of their direction of travel to form a pair of oppositeedges of said bag; and during passage along said defined path,continuously passing an elongated deformable member to, and sealing saidmember on, the face of one of said layers transverse to said edges; andcontinually punching holes through said layers at the points where themember intersects the portion of the layers which are subsequently cutat the cutting station, said layers being cut and sealed to provide asealed bottom edge to said bag and an open top to said bag.
 12. A methodas claimed in claim 11 in which the superimposed layers are passed alongsaid defined path as a tube.
 13. A method of making a recloseable bag offlexible sheet material which comprises continuously passing a pair ofsuperimposed layers of said sheet material along a defined path to asealing station and a cutting station where said layers are sealed andcut transversely of their direction of travel to form a pair of oppositeedges of said bag; and during passage along said defined path,continuously passing an elongated deformable member to, and sealing saidmember on, the face of one of said layers transverse to said edges; andcontinually punching holes through said layers at the points where themember intersects the portion of the layers which are subsequently cutat the cutting station, said layers being cut and sealed to form sideedges of said bag, the superimposed layers being continuously formed bycontinuously longitudinally folding a single sheet of said material toprovide a flap portion on one of said layers extending beyond the otherlayer, said elongated member being sealed on a face of the flap portion.